Here's some cool video of Yamaha actually building these bikes on the assembly line...




In my opinion I believe the bikes shown at the end of the video are the YDS Grand Prix Sports Twin as
shown in the brochure in my post #157.

If you read the comments on U tube their are various comments guessing what these bikes are ?

I think this is the bike that is seen "rolling off" the assembly line and being test ridden
in packs of "roving Yamaha test riders" at the end of the film.



1959-1960 YDS-1Grand Prix Sports Twin....

notice the front brake hub and non twin leading shoe brakes....
as these were a rough magnesium versus the polished aluminum of the YDS-2 and later bikes.

Also the cool almost straight handlebars seem to match ?

Anybody else agree ?

I agree... looks like YDS-1 features all the way through.

Also the video shows a dyno run presumably right off the assembly line? So much for "slow break in"!

That's is a very interesting observation Mark...take a look at the shot at 58 seconds in....the motors appear to be run on a test stand...notice the exhaust attached and what appear to be air ducts. Maybe they are initially tested and broken in....and then the completed bike is then dyno'd at the rear wheel ? As that is what the film seems to depict ?

Long before the Internet even existed I was taught that (at least at some manufacturers) the factory "break in" consists of running the engine hard at full load immediately after a short warm up...

This video might depict that... might not... you decide.

Hey Dave ! Are you still looking for pipes for your YDS ? Try these on for size ! You can pre-heat your fuel and your seat all at the same time.

Yamaha sclambler

orangecounty.craigslist.org/mcy/5235922944.html

Thanks Dave for the post.....

looks like that bike has been out there quite awhile !

Hey at least it has a title.

Have you seen this one? philadelphia.craigslist.org/mcy/5212328192.html

I've been considering it or a DS6C with high pipes in the same price range if a consulting job I'm in the running for pans out

Looks like a very original survivor !

Cool bike....a bit over priced IMHO

Thanks for the post !

One of the interesting things you will notice on the Ascot is the ignition coil wires exiting from the top of the right side case and connecting directly to the sparkplugs



This is possible because of the Hitachi MC-2RY .....twin spark button magneto !

As posted earlier in this thread ....my Ascot motor came with the incorrect ignition installed...
namely a YDS2 generator.

Eventhough the ignition system is hidden beneath the sidecase ....there is no hiding those red coil wires !

So using a PVL or much of anything other than the correct Hitachi magneto will be quite apparent as with most other ignitions require an external coils typically located underneath the gas tank.